A piston is provided with a piston pin to which a small end of a connecting rod is connected. To prevent the piston pin from coming off, a C-shaped clip is fitted into an annular groove of a hole in which the piston pin is installed.
The C-shaped clip fitting operation is manually conducted mainly using long-nose pliers and the like. Since the operation is inefficient, various devices or jigs are proposed to improve the situation.
Patent Document 1 proposes an automatic fitting device comprising an ejecting cylinder, a positioning cylinder, and a fitting cylinder. According to this automatic fitting device, C-shaped clips held within a holder are slantwise pushed into a cylindrical member, one by one, in a reduced diameter condition by the ejecting cylinder. Subsequently, the cylindrical member is lowered by the positioning member to touch a piston, wherein the clip is caused to engage the inside of an annular groove by the fitting cylinder.
Patent Document 2 proposes a device in which a receiving shaft is inserted into an insertion hole for a piston pin, a clip catcher is caused to hold a clip, the clip catcher and a pusher are caused to integrally come close to a piston, the clip held by the clip catcher is transferred to the receiving shaft with a slope, wherein the clip is pushed into the insertion hole by the pusher.
Patent Document 3 discloses a jig in which when a clip is fitted into an annular groove formed in a deep section of a hole for a workpiece, the clip is set on a tapered inlet section of the hole. In this condition, the jig which is concentrically, slidably and integrally formed with a first punch and a second punch is caused to contact the tapered inlet section of the hole, wherein the clip is first pushed into the hole in the reduced diameter condition by the outside first punch and the clip is then pushed into the annular groove formed at the deep section by the second punch.
[Patent Document 1] Japanese Patent Application Publication No. 9-225754
[Patent Document 2] Japanese Patent Application Publication No. 7-068432
[Patent Document 3] Japanese Patent Application Publication No. 2002-292529
According to the fitting device comprising the ejecting cylinder, the positioning cylinder, and the fitting cylinder disclosed in Patent Document 1, it is possible to automatically install the C-shaped clip into the annular groove. However, the device becomes large and it becomes complicated to cope with the change of device.
In the device disclosed in Patent Document 2, it is necessary to operate two jigs of the receiving shaft and the pusher separately. Such a separate operation is troublesome so that it takes time to install the clip on the clip catcher.
In the jig disclosed in Patent Document 3, since the clip must be correctly set on the tapered inlet section of the hole of the opposite member, workability is not good. Further, usability is not good because the jig cannot be used in the case where the inlet section of the hole is not tapered.